Check interactions
Add your supplements, foods, meals — and any medications you take — to see how they interact. Findings are grouped by severity: what to avoid, what needs care or timing, and what actually works better together.
Add more (1/12)
Avoid
4 · Don't combine without medical guidanceVitamin K directly counteracts warfarin — it can restore clotting and raise clot risk.
Why: Vitamin K is the antidote to warfarin; it regenerates the clotting factors warfarin suppresses.
→ Do not start/stop vitamin K without your prescriber; keep intake consistent and monitor INR.
Vitamin K2 counteracts warfarin and can reduce its anticoagulant effect.
Why: Vitamin K regenerates clotting factors warfarin suppresses.
→ Only under prescriber guidance with INR monitoring.
Reduces anticoagulant effect
Why: Same as warfarin - vitamin K antagonism
Reduces anticoagulant effect
Why: Vitamin K antagonist anticoagulant
Caution
48 · Combine carefully — read the noteHigh-dose vitamin E can increase bleeding risk with blood thinners.
Why: Mild antiplatelet effect at high doses.
→ Avoid high doses without prescriber guidance.
Antibiotics kill gut bacteria that produce vitamin K2; may need more K
Why: Reduced intestinal vitamin K synthesis
Can cause vitamin K deficiency; bleeding risk
Why: Interfere with vitamin K recycling
Reduces vitamin K absorption
Why: Binds fat-soluble vitamins in gut
Reduces vitamin K absorption
Why: Blocks fat absorption including fat-soluble vitamins
High vitamin E may interfere with vitamin K function
Why: Competitive inhibition of vitamin K-dependent clotting
Reduces vitamin K absorption
Why: Fat-soluble vitamin binding
Choline (Various Forms): May interact with anticholinergics
Chromium Picolinate: May enhance diabetes meds
Lycopene: May have additive antiplatelet effects with warfarin or antiplatelet drugs (rare, clinical significance unclear)
Nicotinamide Riboside (NR): None significant
Vitamin B1 (Thiamine): Loop diuretics deplete
Vitamin B12 (Cobalamin): Metformin reduces absorption
Vitamin B12 (Cobalamin): PPIs reduce absorption
Vitamin B2 (Riboflavin): None significant
Vitamin D: Glucocorticoids (reduced vitamin D effectiveness)
Vitamin D: Anticonvulsants like phenytoin (increased vitamin D metabolism)
Vitamin D: Orlistat (reduced fat-soluble vitamin absorption)
Vitamin K: Warfarin - must keep intake consistent
Copper: Penicillamine, zinc, antacids reduce absorption
Selenium: May affect thyroid medication needs
Vitamin K2: Warfarin and other coumarin anticoagulants—may reduce anticoagulant effect; consistency is key
Vitamin K2: Some antibiotics (broad-spectrum) may reduce K2 production by gut bacteria
Monitor / Timing
12 · Usually fine — mind timing or watch for effectsMagnesium can bind these drugs and reduce their absorption.
Why: Cation chelation in the gut.
→ Separate magnesium from these medications by 2–4 hours.
Calcium can bind these drugs and reduce their absorption.
Why: Cation chelation in the gut.
→ Separate calcium from these medications by 2–4 hours.
Minimal interaction - does not depend on vitamin K
Why: Direct factor Xa inhibitor - not vitamin K dependent
Minimal interaction
Why: Direct factor Xa inhibitor
Minimal interaction
Why: Direct thrombin inhibitor
May reduce vitamin K levels
Why: Gut bacteria disruption
May reduce vitamin K absorption
Why: Less effect than older agents
May interfere with vitamin K absorption
Why: Competition for absorption
Vitamin D: Magnesium (needed for vitamin D metabolism)
Vitamin D: K2 (complementary for bone and cardiovascular health)
Works well together
33 · Beneficial pairingNicotinamide Riboside (NR) pairs well with Resveratrol.
Vitamin B1 (Thiamine) pairs well with Magnesium.
Vitamin B12 (Cobalamin) pairs well with Folate.
Vitamin B2 (Riboflavin) pairs well with Magnesium.
Bilberry Extract pairs well with Astaxanthin.
